Test for COVID-19 on DBS

Created 05/12/2020 14:03

With support from the Norwegian Research Council, Vitas has developed and validated a test for covid-19 in Dried Blood Spots. The test is ready and shows excellent performance.Vitas has been granted support by the Norwegian Research Council (NFR) to develop and validate a DBS test for covid-19 disease in Dried Blood Spots (DBS). The test is now validated and shows excellent performance (>98% sensitivity and specificity). The test includes a CE marked DBS collection kit as well as a CE marked ELISA kit using spike protein S1 as antigen. An extended validation in 1000 individuals is started 13. May 2020. The purpose is to test the assay in routine, get feedback from users on user friendliness and investigate the rate of infection among these 1000 subjects.

The test will be commercially available soon to private persons through selected partners.If you represent an organization or company and would like a screening of your people, please contact us for an offer or discussion on how to use this product and related services.

Background

The world is in the middle of what probably is the worst pandemic in many decades. Currently (May 12), more than 4.2 million people have been infected and more than 287 000 have died infected by the SARS-CoV-2 virus worldwide. To limit the extent of the infection, reduce the number of people in need of advanced hospital treatment, and to avoid overloading the health care system, Norwegian and international authorities have "closed" many communities. This has led to an unprecedented financial crisis. At the moment, there is limited capacity for monitoring virus infection with SARS-CoV-2, and several places only health personnel and risk groups are tested. Due to the fact that up to about 80% of infected people will have no or just small symptoms, millions of people are in quarantine. Subjects who have been infected, probably exhibit partial or complete immunity, and thus may no longer be infectious.

A person can be infectious from a few days up to about 3 weeks after being infected. Detection of infection is done after sampling in the upper respiratory tract using a gene technology method called polymerase chain reaction (PCR). After about 3 weeks, most people will no longer have virus in their airways, but covid-19 leaves behind a "biological trace" of antibodies to some proteins from the virus. About 7 days after infection, the body starts producing these antibodies against the virus as a defense against new infections.

These antibodies are proteins (immunoglobulins, Ig) found in the blood. First, immunoglobulin M (IgM) is formed and then immunoglobulin G (IgG). These antibodies in the blood can provide full or partial protection (immunity) against new infections with the SARS-CoV-2 virus. Thus, detection of IgM and IgG antibodies against covid-19 in the blood is an excellent way to identify individuals who may get out of quarantine and return to work with reduced or no risk of infecting others or even getting sick again. The assays of antibodies against SARS-CoV-2 virus can be performed using ELISA (enzyme-linked immunosorbent assay) techniques.

It is common to use blood serum or plasma for these assays, which requires that health professionals take venous blood samples from an arm. It also requires centrifugation of the blood in a laboratory or medical office. As an alternative sampling Vitas has been performing similar analyses from so-called Dried Blood Spots (DBS) for 15 years. A drop of blood from the fingertip is deposited on a special paper. The sample can be taken by the subject him/herself at home or at work without a health professional, and it can be sent by regular mail to the laboratory for analysis.

The limited equipment required to take the blood sample is mailed to the subject or purchased at the grocery store or online. This type of distribution is very simple, inexpensive, and allows screening of large populations. The sensitivity of the test, ie subjects proven to have the disease and are found positive by the test, are expected to be between 85 and 95%. This means that out of 100 individuals, 15-5 will be negative for antibodies against SARS-CoV-2 although they have been infected. These subjects must remain in quarantine/ home, and cannot return to work. This does not entail any risk. The specificity of the test, ie persons who have proven not to have had covid-19 disease and who are found to be negative by the test, are expected to be close to 100%. This means that none who has not had covid-19 can go back to work yet.

Important! Only individuals with a positive result (antibodies against SARS-CoV-2 virus) should be able to deviate from current regulations from the government and return to work. People with documented antibodies against SARS-CoV-2 can be considered fit to work or fit to travelThis will be good news for many thousands who are immune to COVID-19 without knowing it, and for many others in the community who depend on these people's manpower. By developing the DBS-based test for antibodies against SARS-CoV-2, Vitas has taken part in the innovation required to reduce the burdens of the pandemic covid-19.